1. Field of the Invention
The present invention relates to an automatic pallet changer, and more particularly concerns an automatic pallet changer whereon a relatively large-sized pallet can be replaced quickly between a pallet table of a machine tool and a pallet magazine storing a number of pallets.
2. Description of the Prior Art
To cope with requirements for automating workshops, there has been developed and is practiced, a system wherein work is placed and fixed on pallets beforehand, and the pallets are fed in sequence to the machine tool.
Where the machine tool is very large, such as a planomiller or the like, the work and the pallet carrying the work are also large in size, and, as compared with an automatic pallet changer (hereinafter called "APC") used for general machine tools, the large-sized tool's APC must have the following points taken into consideration. That is, a work and a pallet being extremely heavy, the driving mechanism must be sufficiently strong to ensure both mechanical strength and driving force. Further, a long-sized pallet entails a prolonged shift stroke, however, as much as possible, accuracy and quickness of replacement should be taken into consideration.